Biography of a Germ

Chapter One: A Very Small Life

To the naked eye, it is invisible, a nothing. Under the microscope, it seems a silvery corkscrew undulating on a dark field. The form has simple elegance, like the whorl of a nautilus shell or the sweep of a dragonfly wing. But that simplicity is an illusion. Through the more powerful electron microscope you see not a featureless wiggle but a shape-shifter -- now a spiral, now a thread, now a rod or a sphere -- with two walls, a dozen whiplike appendages and internal structures. And beyond any microscope's view, revealed only indirectly, by laboratory tests, lies a marvel of complexities. The surface bristles with molecules that sense and respond to the environment, and the interior churns like a chemical factory. Inside, more than a thousand genes flicker on and off in changing sequences, to allow survival in places as different as a tick's gut, a dog's knee and a human brain.

It is the bacterium Borrelia burgdorferi, by human standards a very small, brief flicker of life. Yet the boldest writer of science fiction could not invent a creature so ingenious, whose existence is entwined with that of so many other species. Although this microbe inhabits much of the earth and myriad hosts, it was not discovered until 1982, and then only because it had ignited a new epidemic, Lyme disease. That illness, so troubling to humans, is just a short, recent chapter in the germ's long history, and from its own perspective not the most important one. Borrelia burgdorferi has an ancient lineage, far older than ours, and despite all the vaccines and antibiotics we devise, it has a more promising future. It preceded people on earth and will doubtless survive us. For that reason alone it deserves respectful biographers.

Clearly there is much drama in this little theater. But that should be no surprise, for just as every person's life, seen close up, is compelling, so is every other creature's. Borrelia burgdorferi is proof that if you want to see life afresh and be struck with awe, you need only take a germ's-eye view of the world.